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Neoproterozoic-Early Cambrian continental rifting related to the breakup of the supercontinent Rodinia framed the continental margin of eastern Laurentia and the departing cratons around the opening Iapetus Ocean. The result of continental extension was the production of a zig-zag set of promontories and embayments on the eastern Laurentian margin defined by northeast-trending rift segments offset by northwesttrending transform faults. The St. Lawrence promontory defines the Laurentian margin in western Newfoundland. There, Neoproterozoic-Carboniferous clastic, volcanic, and carbonate successions record protracted continental rifting and passive-margin thermal subsidence followed by destruction of the margin during the early, middle, and late Paleozoic Appalachian orogenic cycles. Palinspastic restoration of deformed Paleozoic strata by a set of balanced cross sections resolves the structure, stratigraphy, and timing of Paleozoic tectonic events on the St. Lawrence promontory. Synrift and post-rift subsidence profiles, as well as abrupt along-strike variations in the age, thickness, facies, and the palinspastically restored extent of synrift and post-rift stratigraphy, indicate the St. Lawrence promontory was founded upon a low-angle detachment rift system. Upperplate margins, lower-plate margins, and transform faults that bound zones of oppositely dipping low-angle detachments are recognized along specific segments of the promontory. A detailed U-Pb and Lu-Hf isotopic detrital zircon study elucidates the identity of specific cratons conjugate to the St. Lawrence promontory in the pre-rift configuration of Rodinia. Approximately 510 zircons from 9 samples collected from basement and overlying Early Cambrian synrift rocks in Newfoundland were analyzed by LA-ICP-MS for U-Pb ages and Hf isotopic ratios. Synrift samples yielded ages ranging from 3605 Ma to 544 Ma with maximum age frequencies of 1000-1200 Ma (Grenville), 1350-1450 Ma (Pinware), and 2650-2800 Ma (Superior), while two basement samples yielded U-Pb ages of 1044 Ma and 1495 Ma. 177Hf/176Hf isotopic ratios of ca.1000 Ma, 1200 Ma, and 1400- 1600 Ma zircons from Newfoundland basement and synrift rocks are a close match to reported 177Hf/176Hf ratios for Baltican zircons of the same vintage, suggesting that Baltica was conjugate to the St. Lawrence promontory.

Detrital monazite Th-Pb and detrital zircon U-Pb and U-Th/He double-dating coupled with sandstone petrography and exhumation rates can be used to test for sediment recycling in Pennsylvanian sandstones within the Alleghenian clastic wedge. The Alleghenian clastic wedge is a logical system in which to test for sediment recycling as four major collisional events (Grenville, Taconic, Acadian and Alleghenian orogenies) likely reworked the continental margin and recycled siliciclastic sediment. The combination of these geochronologic and thermochronologic methods provide a more accurate assessment of the proportion of recycled sediment in the Grundy Formation (sublitharenite) and the Corbin Sandstone (quartz arenite), which past studies and the use of standard zircon U-Pb alone could not distinguish. Recognition of sediment recycling is thus critical for sedimentary provenance studies, which assume a direct path from sediment source to depositional basin. Zircon U-Pb age modes for both formations include the dominant “Grenville doublet” along with a lesser component of Granite-Rhyolite and Taconic age modes. The Corbin Sandstone is temporally more expansive, with age modes associated with the Yavapai-Mazatzal and Kenoran orogenies not present in the Grundy Formation. Monazite Th-Pb age modes are younger than zircon U-Pb for both samples, with dominant modes in the Taconic, Acadian, and Alleghenian, and only minor age modes associated with the Grenville Orogeny. The extent of sediment recycling was quantified by the difference in crystallization ages and exhumation/cooling ages of detrital zircon. This difference in time (∆t) becomes higher in the case of recycling (> ~300 Ma). A median 288 Ma ∆t cutoff value between first-cycle and multi-cycle Grenville aged zircons was calculated using post-Grenville exhumation rates. Furthermore, “detrital diagenetic monazite” grains older than the 312 Ma age of deposition are present in both the Grundy Formation and Corbin Sandstone and proves the occurrence of sediment recycling. In conclusion, most detrital grains of Grenville origin and older are likely multi-cycle, while detrital grains associated with the Taconic, Acadian, Neo-Acadian, and Alleghenian orogenies are likely first-cycle in origin.

Eight fertilization treatments were applied in May 1987 to two sugar maple stands. This was followed by soil and foliar sampling and decline evaluation in mid-summer 1987 and foliar sampling and decline evaluation in mid-summer 1988. / Trees selected for sampling purposes on average showed evidence of light to moderate decline. Foliar nutrient status was found to be poor at both sites, with Ca, Mg, K and P at or very near to deficiency levels although foliar molar ratios for Ca/K, Ca/Mg and Ca/Al were well within their respective critical ranges. / Fertilization had significant effects on several elemental concentrations of the soil and foliage at the Entrelacs sites. Effects in general showed an increase in base cation concentrations when those elements were supplied in high enough quantities in the fertilizers. Fertilization had no significant effect on decline levels. / Positive correlations were obtained between soil B horizon levels and foliar Ca, Mg and K and between soil FH horizon levels and foliar K and Al.

Though the water in eastern Georgian Bay is oligotrophic, some of the coastal embayments and wetlands have begun to show signs of water quality impairment that is thought to be related to human development along the shoreline. The primary objective of my thesis is to provide environmental agencies with the resources to effectively manage water quality in the coastal zone of eastern Georgian Bay. First, I evaluate the ability of the Lakeshore Capacity Model (LCM), developed for inland Precambrian Shield lakes, to predict the trophic status of coastal embayments. Finding that the LCM does not accurately predict trophic status, I develop the Anthro-geomorphic Model (AGM), which uses the level of human development and the degree of mixing between the embayment and open waters of Georgian Bay to predict embayment trophic status. Second, I explore the spatial association between densities of building, dock and road development and Water Quality Index (WQI) scores, an index designed to evaluate wetland condition, for wetlands in the Township of Georgian Bay. I found an inverse relationship between WQI scores and the density of these stressor variables inside wetland catchments, which indicates that these stressors have a negative impact on wetland water quality. I then created a series of mapping products that present building, dock and road densities, along with WQI scores for 61 wetlands in the Township of Georgian Bay, to determine how wetland water quality is spatially associated with densities of these stressor variables. I found that regions with high densities of building, dock and road development were associated with wetlands of lower quality, whereas wetlands in areas that had low densities of development were of higher quality. I used this information to identify areas of conservation priority for management in the Township of Georgian Bay. The results from this thesis will provide environmental managers with resources to protect the valuable coastal waters of eastern Georgian Bay. / Thesis / Master of Science (MSc) / A number of coastal embayments and wetlands of eastern Georgian Bay show signs of water quality impairment thought to be caused by cottage development. The objective of my thesis is to develop and evaluate models designed to measure the impact of human development on water quality in these coastal zones. First, finding that the Ontario Lakeshore Capacity Model, developed for Muskoka lakes, does not accurately predict trophic status in embayments, I develop the Anthro-geomorphic Model, which uses building density and basin morphometry to predict embayment trophic status. Second, I explore the appropriateness of using development densities (building, dock and road) to quantify anthropogenic stress in coastal wetlands. This thesis provides the scientific basis for choosing management practices to protect the coastal waters of Georgian Bay.

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GENERAL ABSTRACT The Laurentian Great Lake wetlands are highly productive and complex systems. The net loss of wetlands since European settlement has been dramatic. The remaining coastal wetlands continue to be threatened with obliteration or severe environmental degradation. Therefore, the overall objective of this study was to provide information on the ecology of the remaining coastal wetlands within the lower Great Lakes. This study describes a coastal wetland fish community along the north shore of Lake Erie within Long Point Marsh complex over a 24-h period and catch characteristics of three common fishing techniques. The fish community was sampled at two hour intervals over a 24-h period in June, and used three types of gear to determine possible sampling biases from the different collection techniques. A total of 497 fish encompassing 11 taxa were collected. A 2-h interval, four hours prior to sunset, netted the largest number of taxa (including 3 functional feeding groups: ornmvores, planktivores, and piscivores ), as well as highest abundance and biomass values. Seine netting demonstrated a biased towards sampling the smaller planktivores, while fyke nets were biased towards larger omnivorous fish, and boat electrofishing was biased towards the large piscivores. These results will assist scientists and lake managers to develop standardized fish sampling protocol in order to accurately assess differences in wetland fish communities. Seven coastal wetlands within Lake Erie and Ontario along both the Canadian and United States shorelines were studied to verify predicted relationships from the literature and determine the relative influences of various habitat features on zooplankton community structure. Water quality, aquatic macrophyte, zooplankton, and fish community information were collected from the wetlands between July 4th and August 2nd of 2001. The predicted relationships from the literature concerning water quality and macrophyte species richness were verified by the results of this work. Water quality and macrophyte species richness were the most accurate predictors of wetland zooplankton community structure. Identifying the wetland characteristics that play primary roles in structuring zooplankton communities will also assist lake managers to make informed decisions of how to most effectively improve zooplankton habitat, to foster larger-bodied zooplankton populations, making the habitat more suitable for larger populations of larval and juvenile fish. / Thesis / Master of Science (MS)

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This thesis proposes that architecture has the potential to organize experience through its sensory effects and that the body is the fundamental link between experience and the imagination. The project in this thesis is a traveling theater. It was inspired by an interest in the intersection between architecture and contemporary theater. The theater borrows elements from traditional theaters and street theater in an effort to establish a separation between actor and spectator while also encouraging exploration of that basic theatrical relationship. There were three fundamental moves in the theater: the cubic volume; the siting and decision to travel; and the separation of the structure and skin. Each of these was a starting point for sensory effects explored in the theater. / Master of Architecture